分子扭曲诱导的单晶异构和性陶转换在一个-二烯复合体中
Ling-Tai Yue1, Svetlana O Shapovalova2, Jie-Sheng Hu1
1Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Liangxiang Campus, Beijing, 102488, China.
Angewandte Chemie (International ed. in English)
|March 7, 2024
概括
一种新型的复合物 ([Co(pycz) 2 ((Sq) 3)) 呈现出一种独特的单晶转化为异构体 ([Co(pycz) 2 ((Sq) 3)) 具有明显的价值定体 (VT) 特性,为VT材料提供了新的控制.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
背景情况:
- 单核复合体中的价值分离体 (VT) 是开发可切换材料的关键现象.
- 在VT化合物中控制固态结构转换仍然是一个重大挑战.
研究的目的:
- 合成和描述一种能够进行结构转换的新型单核复合物.
- 为了研究母体和转化复合体的价值对称性行为.
- 阐明观察到的结构转变背后的机制.
主要方法:
- 一个单核复合物的合成 [Co(pycz) 2 ((Sq) ((Cat) ] (1-trans).
- 在现场单晶X射线衍射来监测结构转变.
- 磁性测量以研究价值定体过渡.
- 密度函数理论 (DFT) 计算以了解转换机制.
主要成果:
- 转变异构体 ([Co(pycz) 2 ((Sq) ((Cat)]) 在室温以上经历一阶段的VT过渡.
- 一个新的单晶到单晶转换到cis同位素 ([Co(pycz) 2 (((Sq) ((Sq)) 在350K以上通过分子扭曲发生.
- 这种cis异构体表现出一种罕见的两步VT过渡,与父复合体不同.
- 转变是由一个晶体表面化-再结晶过程驱动的.
结论:
- 已经证明了一种诱导VT综合体结构转型的新策略.
- 观测到的转换允许调整和控制值 tautomeric 属性.
- 这项工作为设计具有定制功能的先进可切换材料开辟了道路.
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